Vitamins Vitamin A Vitamin B Vitamin C Vitamin D Vitamin E Beta Carotene Lutein Lycopene Folic Acid Profiles

Vitamin D Turn-around time = 5 to 7 days. Specimen required is 0.5 mL of serum protected from light and mailed in an amber plastic tube. Vitamin D is one of the fat-soluble vitamins, along with A, E, and K. Its metabolites can be classified into two families, the cholecalciferols and ergocalciferols. Cholecalciferol (vitamin D3), is the parent of the naturally occurring family and is produced in the skin on exposure to sunlight. The UVB portion of sunlight (290 to 315 nm) converts 7-dehydrocholesterol (provitamin D3) to vitamin D3, cholecalciferol. The liver converts D3 to 25-hydroxycalciferol (25-OH-D). The main function of vitamin D in the body deals with calcium absorption, transport, deposition and metabolism. Decreased levels can result in symptoms involving disturbed calcium use, nerve and muscle impairment, soft or fragile bones, or if severe enough, in the classic disease called rickets. An excellent source of vitamin D is sunshine on skin, 15 to 20 minutes a day. Other sources of vitamin D are butter, eggs, milk, cod liver oil and cold water fish. The RDA for vitamin D is 600 I.U. A suggested supplemental level is 600 to 1000 I.U. 2000 I.U./day can lead to toxicity. The methodology is by RIA. The normal value established in our laboratory is 15 to 47 ng/mL. Selected References: Chesney RW: Current clinical applications of vitamin D metabolite research. 1981; Clinical Orthopedics and Related Research; 161:285. DeLuca HF, Schnoes HK: Metabolism and mechanism of action of vitamin D. 1976; Annual Reviews in Biochemistry; 45:631. Clemens TL.: Vitamin D: Recent advances in basic research and clinical assay Methodology. 1986; Journal of Clinical Immunoassay; 9(4):183. 4. Prece MA, Tomlinson CA, et al: Studies of vitamin D deficiency in man. 1975; Q J Med.;44:575. 5. Tietz Textbook of Clinical Chemistry, 3rd Ed., 1999, Saunders Company:p1004 Back to Vitamin Home Page

---

[Search] [Home] [About Us] [Why Bio-Center?] [Lab tests] [Order Test Kits] [FAQ] [Contact Us]

---

Back To Bio-Center Lab

This website is managed by The Center For The Improvement Of Human Functioning International
A Non-profit Medical, Research and Educational Organization
3100 North Hillside Avenue, Wichita, KS 67219 USA
Phone: 316-682-3100; Fax: 316-682-5054
© (CIHFI) 2008

This website and all contents are Copyright: 1997/2008 CIHFI - All Rights Reserved.